[nas t eh]

My rear glass is in poorer shape than I would like, Is anyone reproducing this part with the electric rear defrost wires?

[VCho455]

This may be an option for you. I've never used them but they have been around for at least a decade.

https://frostfighter.com/clear-view-...ters-about.htm

[Trevor78]

Off topic, how successful were the rear defogger fans? Obviously they were replaced by the grids fairly quickly.

[VCho455]

I put one in my 69 GTO when it was my daily driver. Not exact apples to apples comparison but... I mounted in the center of the package tray between the speakers. During my normal 15 minute commute to work in the first 5 minutes it would have about a 12 inch circle clear in the middle of the window and by the time I got to work it would usually have the passenger side of the window mostly clear. However the drivers side takes much longer to clear.

That is likely a result of the design of the blower grille. I got the unit out of a 74/76 Bonneville and there it was mounted on the drivers side of the package tray with most of the air blowing across towards the passenger side. I wasn't going to swap the blower and the speaker for better defogging, so I lived with it as it was better than nothing.
As the odds of me finding a 70/74 electric rear window with the controls are pretty much zero, I am seriously considering getting one of the aftermarket units I posted for my 72. Here in NW Oregon defoggers are a must have.

[Dave R]

Originally Posted by Trevor78

Off topic, how successful were the rear defogger fans? Obviously they were replaced by the grids fairly quickly.

I drove as a daily driver a 70 TA without a blower, a 70 TA with a blower and a 73 Formula 455 with the electric grid. We get a lot of rain in winter and sometimes summer and I can tell you the first was useless, the second kind of ok for seeing behind you after 10 minutes or so but the edges were foggy even on longer drives and the 73 cleared in a few minutes. Night and day difference.

[Dave R]

Originally Posted by nas t eh

My rear glass is in poorer shape than I would like, Is anyone reproducing this part with the electric rear defrost wires?

Would love to see this window reproduced in tinted glass as they were hard to get even years ago.

There is a procedure in the body shop manual for repairing the grid if all the lines aren’t working.

[unruhjonny]

I am only replying now because I just came across this discussion;

Originally Posted by Trevor78

Off topic, how successful were the rear defogger fans? Obviously they were replaced by the grids fairly quickly.

My understanding is that they each serve a distinctly different purpose - even though practically speaking, there is overlap.

The fan was for defogging the inside of a rear window, much like your front windshield defog.
The heat grid was for clearing off the outside of the glass in frozen temperatures.

I think everyone will agree that the heat grid is generally better because it warms the glass, and in doing so, it can clear away any condensation on the inside of the glass - that is the overlap.

Originally Posted by Trevor78

... Obviously they (fan/defog) were replaced by the grids fairly quickly.

One type was never intended to replace the other type - but the fan (defog) style was a much cheaper cost option, and easier to maintain and repair (it uses the same blower fan that is at your heater box), while the heat grid can be a pain to repair if it's not working properly.

Sales code / UPC code - description: price in 1972 (price in todays $$)
541 / C50 - Defogger, Rear-window: $31 ($228)
534 / C49 - Defroster, Rear-window, Electric: $62 ($456)

[Peter Serio]

The Repair kit referenced in post #6 above:

I used to use this to repair a scratched line or 2 on the inside of the back glass.